The calculations enable the user to design reinforcement in concrete finite elements so that the crack widths resulting from applied loading (bending and axial forces) and temperature and moisture effects are limited to acceptable values.
The module can either:
- Calculate the reinforcement required to limit the crack width to a user defined value
- Calculate the crack width resulting from any arrangement of reinforcement
The caclculations are based on BS 8007:
- Appendix A - "Calculation of minimum reinforcement, crack spacing and crack widths in relation to temperature and moisture effects"
- Appendix B - "Calculation of crack widths in mature concrete"
Crack widths are always calculated according to both Appendices and the maximum value is displayed or used to calculate reinforcement.
The calculations is carried out as follows:
- The program calcualtes the reinforcement required to staisfy moment/force the requirements (using factored load combinations).
- The program then calculates minimum reinforcement requirements according to Code Appendix A (wmax < allowable) and revises the reinforcement, if necessary.
- The program then calculates the crack width based on service load requirements of Code Appendix B. The program increases the reinforcement if the width is greater than the limiting crack with parameter specified by the user (if the
option is selected by the user).
Results (crack widths and reinforcement) may be displayed in the following formats:
Tubular (per element):
A summary sheet is also available.